21533673399 has 16 divisors (see below), whose sum is σ = 32815279872. Its totient is φ = 12304182528.

The previous prime is 21533673397. The next prime is 21533673419. The reversal of 21533673399 is 99337633512.

It is a happy number.

It is not a de Polignac number, because 21533673399 - 2¹ = 21533673397 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21533673397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 580792 + ... + 616754.

It is an arithmetic number, because the mean of its divisors is an integer number (2050954992).

Almost surely, 2^21533673399 is an apocalyptic number.

21533673399 is a deficient number, since it is larger than the sum of its proper divisors (11281606473).

21533673399 is a wasteful number, since it uses less digits than its factorization.

21533673399 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64486.

The product of its digits is 2755620, while the sum is 51.

The spelling of 21533673399 in words is "twenty-one billion, five hundred thirty-three million, six hundred seventy-three thousand, three hundred ninety-nine".